Three-Dimensional Ordered CeO2 Hollow Spheres (3DOHSs-CeO2) from Polymethylmethacrylate/CeO2 Core/Shell Microsphere Colloidal Crystals

摘要

The composite microspheres containing polymethylmethacrylate (PMMA) cores and ceria (CeO2) nanoparticles shells were synthesized by in situ chemical precipitation based on electrostatic interaction. The PMMA/CeO2 colloidal crystal templates were self-assembled by a modified two-substrate vertical deposition method. After removal of the polymer cores by calcination, the three-dimensional ordered CeO2 hollow spheres (3DOHSs-CeO2) films were fabricated. The resulting 3DOHSs-CeO2 materials were characterized by X-ray diffraction, field emission scanning electron microscopy, high resolution transmission electron microscopy, and N-2 adsorption-desorption analysis. Results indicate that the obtained samples presented a typical face-centered cubic structure, and the CeO2 hollow spheres (HSs) formed shared necks with each other. The average CeO2 HSs diameters and center-to-center distances were 230-240 nm, and the porous shells (20-30 nm in thickness) of CeO2 HSs were consisted of tiny CeO2 nanoparticles with a size of 10-20 nm. This work suggested that the 3DOHSs architectures would be valuable for photonic crystals, advanced optical and catalytic applications.